1. Field of Invention
The present invention relates to a pneumatic tool and, more particularly, to an inexpensive pneumatic tool.
2. Related Prior Art
In Taiwanese Patent Publication No. 513992, there is disclosed an air-directing device of a pneumatic tool. This pneumatic tool includes a shell 20 defining spaces 21 and 26, a cylinder 23 put in the space 21, a rotor 22 put in the cylinder 23, a sleeve 32 put in the space 26, and a rotational switch 33 put in the sleeve 32 except an end by which the rotational switch 33 can be rotated. The air-directing device is made of the sleeve 32 and the rotational switch 33. The rotational switch 33 includes blocks 331–334. The sleeve 32 includes aperatures 321–325. As the rotational switch 33 is rotated in the sleeve 32, the blocks 331–334 are rotated relative to the apertures 321–325. Thus, the direction and rate of the rotation of the rotor 22 is changed. It is, however, troublesome and, hence, expensive to independently make the sleeve 32 and then to fit it in the space 26. Moreover, it is difficult and, hence, expensive to make the apertures 321–325 in the sleeve 32 and form the blocks 331–334 on the rotational switch 33.
In Taiwanese Patent Publication No. 367926, there is disclosed a controlling and regulating device for a pneumatic tool. This pneumatic tool includes a shell 40 defining spaces 41 and 45, a rotor (not shown) put in the space 41, and a rotational switch 70 put in the space 45 except an end by which the rotational switch 70 can be rotated. The rotational switch 70 includes two channels 711 and 712 and two slots 714 and 715. The channels 711 and 712 are communicated with and extended perpendicular to each other. As the rotational switch 70 is rotated, the channels 711 and 712 and the slots 714 and 715 are rotated. Thus, the direction and rate of the rotation of the rotor is changed. However,it is difficult and, hence, expensive to make the channel 711 and 712 that are communicated with and extended perpendicular to each other. Furthermore, it entails a cost to make the slots 714 and 715.
The present invention is therefore intended to obviate or at least alleviate the problems encountered in the prior art.